Self-piercing stud and post for snap fasteners



May 4 1926.

G. A. KING SELF PIERCING STUD AND POST FOR SNAP FASTENERS Filed Feb. 5,1926 "Ill/Ill] June n #04:

Patented May 4, 1926.

- UNITED STATES PATENT OFFICE.

GEORGE A. KING, OF WATERBUI BY, CONNECTICUT, ASSIGNOB T0 SCOVILLMANUFAC- TURING COMPANY, OF WATERBU'RY',

NECTICUT.

SELF-'PEBCING STUD AND ros'r non sues FASTENERS.

CONNECTICUT, A CORPORATION OF CON- Application med February a, 1926.Serial No. 85,702.

To all whomit may concern:

Be it known that I, Gnonen A. KING, a citizen of the United States,residing at Waterbury, in the county of New Haven and State ofConnecticut, have invented a certain new and useful Improvement in Self-Piercing Studs and Posts for Snap Fasteners, of which the following is a.full, clear, and exact description.

The object of this invention,.pri.marily, is to provide a self-piercingmember of a snap fastener or separable fastener, which is adapted topierce the fabric on which it is applied in the operation of setting thedevice, and therefore is self-piercing as that term is herein used, asdistinguished from those devices in which it is necessary to use aseparate tool, implement or machine for perforating the fabricpreliminarily to and for the purpose of setting the fastening member. 1

It is not broadly new at this time to provide self-piercing fastenermembers, but so far as I am aware, such self-piercing members areadapted for use only in connection with thin material, such as silkfabric and the like, and I am not aware that the selfpiercing principlehas hitherto been made available for use for such fasteners on thick andheavy fabric, such as rubber, and laminated fabrics such as argused inarctic overshoes and other articles.

In my eflorts to adapt the self-piercing principle to snap fasteners foruse on such eavy material, I have obtained entirely satisfactory andpracticable results by inwardly knurling the neck portion of the head orstud and sharpening and outwardly flaring the leading end of the barrelof the atteaching post to such an extent that the outside diameter ofsuch flared end will exceed by a few thousandths of an inch the internaldiameter of the knurled neck, and then when these parts are assembled onopposite sides of a fabric and pressure applied to unite the parts, theflared end when forced through the fabric will be engaged by the saidneck and saidflared end of the post will be reduced in diameter as itpasses up into the head or stud and will be curled inwardly or outwardlywithin the head or stud so as to securely clinch and thereby unite theparts of the fastener on the fabric, the cutand the leadin out portionof the fabric escaping outwardly through the barrel of the post.

The invention consists of a self-piercing stud and post for snapfasteners having a y construction and mode of operation such as justdescribed, as I will proceed'now to explain and finally claim. 1

In the accompanying drawings illustrating the invention, in t e severalfigures of which like parts are similarly designated, Figure 1illustrates the head or stud and the post, in cross-section, arranged onopposite sides of a piece of fabric, as they will be preliminarily tobeing pressed together for piercing the fabric and uniting the parts.Fig. 2 is a similar view showing the parts in the act of piercing thefabric. Fig. 3 is a similar view showing the'fabric pierced end of thepost inside of the head or stu and beginning to be curled. Fig. 4 is asimilar view showing the parts set, with the leading end of the postcurled inwardly. Fig. 5 is a view similar to Fig. 4, but with theleading end of the post curled outwardly; Figs. 4 and 5 show the devicein its finished form as applied to the fab-- 1'10.

The drawings show the parts enlarged but the proportions aresubstantially correct.

' The invention is here illustrated and will be explained in connectionwith a rigid head or stud 1, having the reentrant top 2, inwardlyknurled neck 3 and flange 4. The inside diameter of the knurled neck isless than the inside diameter of the top portion of the head or stud.

barrel 5, open. at both ends, the leading end 6 of which is flaredoutwardly and its extremity 7 made as a cutting edge, the diameter ofwhich is a few thousandths of an inch less than the internal diameter ofthe knurled neck of the head or stud. The barrel 5 rises from a base orflange 8 which may be provided with embossments-9 "to engage the fabricto prevent rotation of the parts.

When the parts are brought into juxtaposition on opposite sides of thepiece of fabric or a garment, 10, in the manner indicated in Fig. 1 andpressure is applied in the direction of the part 10, the cutting edge 7will pierce the member 10 in cooperation with the resistance offered bythe head or stud, as illustrated in Fig. 2, and suchpressure beingcontinued the post will be driven into the cavit of the head or studpast the neck of the ead or stud and the cutting edge coming in contactwith the wall of the top of the head or stud will be curled eitherinwardl as indicated in Figs. 3 and 4, or outwardl .as indicated in Fig.5, until the base-or ange 8 of the post is brought into contact with thefabric or garment 10 and thereby the head or stud and post are firmlysecured together and to the fabric-or garment.

The pieceof material 11 cut from the fabric or garment, is not carriedup into the head or stud, but enters the post, as shown in Figs. 2 and3, and is free to fall out of the post. This separation of the cut-outportion and its elimination from the head or stud is of materialadvantage in effecting secure clinching and union of the stud and 0st,since it offers no obstruction to the efective curling or clinching ofthe leading end of the dpost within the heador stud.

As alrea sufliciently indicated, the leading end of t e post ispurposely made sharp to form an ideal shearing surface in connectionwith the neck of the head -orstud, which, during this operation servesas a support or bearing for the cutting edge within the stud, thusenabling the cutting through or clean-cut piercing of the material,-aresult which is not always or uniformly attained when the leading edgeof the post is not flared and the post itself is not hollow or tubular.

As already stated, the invention herein is designed for use particularlyon thick fabrics, such as rubberized material used in arctic overshoes,which is very hard to selfpierce with a straight barrel post. By the useof the slightly flaring leading end of the post to increase the diameterof the post, and the use of a head or stud with an inside diameter atthe neck a few thousandths of an inch less than the diameter of thesharp end of the 0st, there are obtained coacting cutting sur aces whichmay be relied upon to out clean the material around the wholecircumference of the desired hole. In this way, none .lows a moreperfect chamber for the of the material so cut out is carried up intothe head or stud, and the absence of this cut out material from the headorstud al- 0st to rivet in under pressure of the tools or dies, andpractically eliminates any possibility of the disengagement of the twoparts or members of the fastener after they have been once set inposition by the dies.

The illustration of my invention herein contained is in the form of themale member of a stud and socket fastener or a snap fastener. f

What I claim is l. A male member of a stud and socket fastener or a snapfastener, comprising a stud having a knurled neck and a post having itsleading endoutwardly flared and sharpened and adapted in'cooperationwith the knurled neck of the stud to cut through the material on whichit and the stud are set and thereafter be clinched within the stud.

2. A male member of a stud and socket fastener or a snap fastener,comprising a stud having a knurled neck and a post having its leadingend outwardly flared and sharpened and of greater diameter than theinside diameter of the neck of the stud and adapted to cooperate withthe knurled neck to cut-its way through the material on whichthefastener is used and thereafter be clinched Within the stud.

3. A self-piercing stud and post for snap fasteners, the stud having aknurled neck GEORGE A. KING.

